a) Don't use POSIXlt in data frames... use POSIXct. POSIXlt is like a data frame of its own, and data frames within data frames lead to surprising results, to say the least.
b) I have had best luck using Sys.setenv( TZ="Etc/GMT+8" ) for US Pacific Standard Time as "local" time for the duration of analysis. c) Use the format argument if you want consistent results. --------------------------------------------------------------------------- Jeff Newmiller The ..... ..... Go Live... DCN:<jdnew...@dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/Batteries O.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...1k --------------------------------------------------------------------------- Sent from my phone. Please excuse my brevity. pdb <ph...@philbrierley.com> wrote: >I have a data frame that contains dates, but when I use as.POSIXlt() I >lose >the hours on all records. I traced this down to a particuar hour which >causes the issue... > >> as.POSIXlt('2004-10-31 02:00:00') >[1] "2004-10-31" >> as.POSIXlt('2004-10-31 03:00:00') >[1] "2004-10-31 03:00:00" > >How do I tell as.POSIXlt() to ignore daylight savings and just convert >to a >time as is? I've read about the 'isdst' but it is still unclear what to >do. > >This is a cleaned up date field that I received so adjusting the date >itself >is not possible. > >Thanks in advance. > > > >-- >View this message in context: >http://r.789695.n4.nabble.com/POSIXlt-and-daylight-savings-time-tp4642253.html >Sent from the R help mailing list archive at Nabble.com. > >______________________________________________ >R-help@r-project.org mailing list >https://stat.ethz.ch/mailman/listinfo/r-help >PLEASE do read the posting guide >http://www.R-project.org/posting-guide.html >and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.